Transverse single-spin asymmetry and cross section for π0 and η mesons at large Feynman x in p↑+p collisions at √s=200 GeV

Scientific paper - Original scientific paper

• Author: L. Adamczyk
• Author: ...
• Author: Mirko Planinić
• Author: ...
• Author: Nikola Poljak
• Author: ...
• Author: Y. Zoulkarneeva
• Collaboration: STAR Collaboration
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

Measurements of the differential cross section and the transverse single-spin asymmetry, AN, vs xF for π^0 and η mesons are reported for 0.4<xF<0.75 at an average pseudorapidity of 3.68. A data sample of approximately 6.3  pb^−1 was analyzed, which was recorded during p↑+p collisions at √s=200  GeV by the STAR experiment at RHIC. The average transverse beam polarization was 56%. The cross section for π^0, including the previously unmeasured region of xF>0.55, is consistent with a perturbative QCD prediction, and the η/π^0 cross-section ratio agrees with existing midrapidity measurements. For 0.55<xF<0.75, the average A_N for η is 0.210±0.056, and that for π^0 is 0.081±0.016. The probability that these two asymmetries are equal is ∼3%.

• Keywords (english): spin; asymmetry; meson; STAR
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Physical Review D - Particles, Fields, Gravitation and Cosmology
• Numbering: vol. 86, no. 5, 051101(R)
• p-ISSN: 1550-7998
• e-ISSN: 1550-2368
• DOI: https://doi.org/10.1103/PhysRevD.86.051101
• URN:NBN: urn:nbn:hr:217:766255
• Publication: 2012
• Project: Number: 119-0982887-1006; Title (croatian): Istraživanje hadronskih sustava upotrebom relativističkih projektila; Leader: Mirko Planinić; Jurisdiction: Croatia; Funding stream: ZP
• Document URL: http://link.aps.org/doi/10.1103/PhysRevD.86.051101
• Type of resource: Text
• Access conditions: Open access
• Public note: Copyright (2012) by the American Physical Society. Received 1 June 2012; published 5 September 2012.
• Created on: 2019-11-19 20:04:23